Plan the investigation
What students will do
Start with a guided comparison, then plan an investigation, analyze a graph, and check a prediction.
- Compare speeds. Measure speed and string tension for the handout’s initial trials at the same radius and mass.
- Design and collect. Choose at least five speeds. Keep mass and radius fixed and plan consistent tension measurements.
- Analyze a linear graph. Transform the speed data, draw a best-fit line, and interpret its slope using the circular-motion model.
- Explain and predict. Explain the acceleration despite steady speed, then predict and test tension at an unused speed.
What students will learn
- Distinguish speed from velocity in curved motion.
- Identify string tension as an inward force.
- Test the speed-squared dependence of centripetal force.
Common misconception
Can steady speed mean nonzero acceleration?
The velocity direction changes around a circle, so an inward acceleration is required.